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hMPV Is a pathogen that emerged as a result of increased and tenacious diagnostic efforts rather than through expansion of it range or transmission to a new host speciesIs a pathogen that emerged as a result of increased and tenacious diagnostic efforts rather than through expansion of it range or transmission to a new host species First identified in 2001 by van den Hoogen BC, et al. (Nat Med 2001;7:719)First identified in 2001 by van den Hoogen BC, et al. (Nat Med 2001;7:719) Isolated from 28 young children, stored nasopharyngeal aspiration (NPA) with RTI over 20 years in NetherlandsIsolated from 28 young children, stored nasopharyngeal aspiration (NPA) with RTI over 20 years in Netherlands –New member of Metapneumovirus genus, Paramyxoviridae family

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Phylogeny of hMPV Indicator for the relationship between the newly identified virus isolates and members of PneumovirinaeIndicator for the relationship between the newly identified virus isolates and members of Pneumovirinae Phylogenetic trees were constructed based on the N, P, M and F ORFs of these virusesPhylogenetic trees were constructed based on the N, P, M and F ORFs of these viruses

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Year of study – vary by year or location “periodic epidemics”Year of study – vary by year or location “periodic epidemics” –North America study: more frequent in 2001 than 2000 (7% vs.1.5%) –Italian study: more frequent in 2002 and 2000 than 2001 (43%, 37% vs.7%) –African study: more frequent in 2002 than 2001 and 2003 (19% vs. 7.7%, 2.2%) SeasonalitySeasonality –Temperate region: late winter to spring –Subtropics region: late spring to summer (HK) Epidemiology of hMPV

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Comparison of hMPV and RSV (1) Overall, hMPV is less commonly isolated from respiratory specimens than RSVOverall, hMPV is less commonly isolated from respiratory specimens than RSV RSV appears more common than hMPV in infants <6 monthsRSV appears more common than hMPV in infants <6 months Similar to RSV, majority of hMPV cases occur in young ( 65 yrs)Similar to RSV, majority of hMPV cases occur in young ( 65 yrs) hMPV peaks later (April), where as RSV peaks earlier (December-February)hMPV peaks later (April), where as RSV peaks earlier (December-February) hMPV and RSV have similar clinical presentation in children and elderlyhMPV and RSV have similar clinical presentation in children and elderly In 1 study (Greensill J, et al. Emerg Infect Dis 2003;9:372), hMPV/RSV coinfection was detected in 70%In 1 study (Greensill J, et al. Emerg Infect Dis 2003;9:372), hMPV/RSV coinfection was detected in 70%

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Comparison of hMPV and RSV (2) While both hMPV and RSV can provokes severe infections, disease severity and hospitalization appears more common with RSVWhile both hMPV and RSV can provokes severe infections, disease severity and hospitalization appears more common with RSV –Compared the clinical symptoms hMPV with age- matched RSV infected children; RSV-infected found more dyspnea, hypoxemia and feeding difficulties –Two studies in hospitalized patients show that hMPV did not need PICU, contrast to some of RSV and Influenza-infected patients 1,2 –Pneumonia was more often associated with RSV 1. Viazou S, et al. J Clin Microbiol 2003;41: Boivin G, et al. Emerg Infect Dis 2003;9:634.

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CA-MRSA: Definition CDC: diagnosis made in the community setting or by culture positive for MRSA within 48 hrs after admission to hospitalCDC: diagnosis made in the community setting or by culture positive for MRSA within 48 hrs after admission to hospital –It is known that patients may be colonized with HA-MRSA for year before developing infection –Nosocomial outbreak of CA-MRSA have been reports (MMWR Mar 31, 2006;55:329)

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Methicillin Resistance Altered penicillin-binding proteins (PBP2a) that had markly reduced affinity for all beta-lactam antibioticsAltered penicillin-binding proteins (PBP2a) that had markly reduced affinity for all beta-lactam antibiotics PBP2a is encoded by the mecA gene which carried on the mobile DNA element (the staphylococcal cassette chromosome mec (SCCmec)PBP2a is encoded by the mecA gene which carried on the mobile DNA element (the staphylococcal cassette chromosome mec (SCCmec) The other important component of SCCmecThe other important component of SCCmec –The chromosome cassette recombinase (ccr) genes encodes for proteins that enable precise intregation into and excision from specific site of S. aureus chromosome (attBscc) Foster TJ. J Clin Invest 2004;114:1693

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CA-MRSA: Epidemiology Four pediatric deaths from CA-MRSA – Minnesota and North Dakota, (MMWR, Aug :48;707)Four pediatric deaths from CA-MRSA – Minnesota and North Dakota, (MMWR, Aug :48;707) Case reportsCase reports –7-year-old black girl with high fever and Rt groin pain, she underwent surgical drainage for Rt hip infection and treated with cefazolin. On 3 rd day antimicrobial was changed to vancomycin when cultures of blood and joint fluid grew MRSA. Her course was complicated by ARDS, pneumonia and empyema. She died from pulmonary hemorrhage after 5-weeks of hospitalization

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Case reports (cont.)Case reports (cont.) –16-month-old girl with shock, high fever, seizure, diffuse petechial rash. She was treated with ceftriaxone but developed respiratory failure and cardiac arrest and died within 2 hours –13-year-old girl with fever, hemoptysis and respiratory distress. CXR revealed LLL infiltrate and pleural effusion. She was treated with cefriaxone and nafcillin. Within 5 hours of arriving at hospital, she become hypotensive and was intubated and treated with vancomycin and cefotaxime. She died on the 7 th hospital day from cerebral edema and MOFS –12-month-old boy with bronchiolitis, vomiting, and dehydration. He had high fever and petechial rash. On 2 nd hospital day he has large Rt pleural effusion and treated with vancomycin, cefuroxime and ICD. He developed respiratory failure and hypotension the following day and died

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CA-MRSA: Epidemiology 1,002 MRSA cases were CA-MRSA 982 cases (92.6%)1,002 MRSA cases were CA-MRSA 982 cases (92.6%) Mean age was 7.9 years and 51.3% were maleMean age was 7.9 years and 51.3% were male Number of MRSA case/year was 43 cases in 2000 to 467 cases in 2003, this increase was solely by rise in number of CA-MRSA infectionNumber of MRSA case/year was 43 cases in 2000 to 467 cases in 2003, this increase was solely by rise in number of CA-MRSA infection Purcell K, et al. Arch Pediatr Adolesc Med 2005;159:980

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Conclusions Available evidence suggests that CA-MRSA is an emerging problem in pediatricsAvailable evidence suggests that CA-MRSA is an emerging problem in pediatrics Clinicians should be aware that therapy with beta-lactam antimicrobials can no longer be relied on as the sole empiric therapy for severe illness patients whose infections may be CA-MRSAClinicians should be aware that therapy with beta-lactam antimicrobials can no longer be relied on as the sole empiric therapy for severe illness patients whose infections may be CA-MRSA What is the CA-MRSA situation in Thailand?What is the CA-MRSA situation in Thailand?